Exemplary embodiments relate to an electrophoretic display and a method of manufacturing the same.
In the related art, reflective displays that are viewable under a surrounding natural brightness can offer usability close to that of printed matters. Electrophoretic displays, which do not need polarizers and have a high efficiency with the use of light, can be used as such reflective displays.
In electrophoretic displays, for example, a pair of substrates, at least one of which is a transparent substrate, is disposed facing each other. A dispersion liquid including particles (electrophoretic particles) that are electrophoresed by application of electric field is disposed between these substrates.
Examples of the electrophoretic displays are disclosed in Japanese Unexamined Patent Publications No. 2003-295234 and No. 2003-295235, for example. In these techniques, microcapsules filled with a dispersion liquid, that includes white-colored particles positively charged and particles that are colored in a different color and are negatively charged, are disposed between substrates having electrodes. Then, the color viewed from the viewing side (transparent substrate side) is changed by varying the polarity of one or the other electrode. Specifically, when a negative voltage is applied to the electrode on the viewing side, the positively charged particles (white particles) are electrophoresed toward the transparent substrate side by means of the Coulomb force so as to attach to the electrode of the viewing side. When the display in this state is viewed from the transparent substrate side, a part in which the particles have been attached to and a layer that has been formed looks white. In contrast, when the polarity of an applied voltage is reversed, the particles positively charged (particles colored in a different color) attach to the electrode on the viewing side so as to form a layer, so that the display shows the color.
In addition, in another related art electrophoretic display, a non-transparent substrate is colored in a color different from that of particles. Then, a voltage having the polarity opposite to that of the particles is applied to an electrode between substrates, whereby the particles are attached to the electrode. Thus, the color of the non-transparent substrate is displayed. In contrast, a voltage is not applied to the electrode so that the particles are deposited on the non-transparent substrate, and thus displaying the color of the particles.
In still another related electrophoretic display, a dispersion liquid including particles is filled into microcapsules colored in a different color from that of the particles. Then, a voltage having the polarity opposite of that of the particles is applied to an electrode disposed on a transparent substrate, whereby the particles are attached to the electrode on the transparent substrate. Thus, the color of the particles is displayed. In contrast, a voltage having the polarity opposite to that of the particles is applied to an electrode disposed on a non-transparent substrate so that the particles are attached to the electrode on the non-transparent substrate, and thus displaying the color of the microcapsule.
Related art devices are disclosed in Japanese Unexamined Patent Publication No. 2003-295234, Japanese Unexamined Patent Publication No. 2003-295235, and WIPO Patent Publication No. WO00-54101.